Summary The Bell 205 A-1 helicopter (registration C-GADA, serial number30031), with a pilot and a loadmaster on board, was engaged in forest fire suppression operations at Solitude Lake, Quebec, about 25 nautical miles northwest of Port-Cartier, Quebec. At approximately 1220 eastern daylight time, the helicopter hover taxied from a fuel cache site located at the south end of the lake. The helicopter was slinging an empty water bucket on a 100-foot longline. While decreasing power to bring the helicopter to a hover, the pilot felt a vibration, followed by a loud bang, and what seemed to be a loss of power. The helicopter quickly lost altitude and pitched nose down and to the right before striking the water. The pilot and loadmaster managed to exit the helicopter while it was sinking and were rescued by nearby firefighters. The pilot-in-command was seriously injured. The loadmaster sustained minor injuries. The helicopter was substantially damaged. Ce rapport est galement disponible en franais. Other Factual Information The helicopter was owned and operated by Hli-Express Inc. The pilot-in-command was certified and qualified for the flight in accordance with existing regulations and was operating in visual meteorological conditions. He had approximately 8000hours of total flying time, with 60hours on the Bell205. He had completed his training and pilot proficiency check on the Bell205 on 07July2005 and occupied the position of chief pilot. The helicopter was equipped with a vertical reference kit (with bubble window) that allowed the pilot to operate the helicopter from the left seat while watching the load and longline. The loadmaster, seated in the right seat, held a commercial helicopter licence but was not type rated on the Bell205. He was on board as an observer for longline aerial operations training. He was not at the controls at the time of the occurrence. As a low-time pilot, he was hired by the company to help with secondary duties such as loading passengers, preparing cargo nets, and fuelling. On 15 July 2005, the Bell205 was flown to a base camp 25nautical miles north of Port Cartier to conduct forest fire duties. The morning of July16, the helicopter was flown to the fuel cache situated along the river to the south end of Solitude Lake and then returned to base camp. The 100-foot longline was connected to the helicopter. The helicopter then conducted two cargo net flights before returning to base camp. At approximately 1100 eastern daylight time,1 a portable fuel pump and water bucket were boarded before departing for the fuel cache where the helicopter was refuelled with approximately 1000pounds offuel. At approximately 1210, the water bucket was connected to the 100-foot longline. The helicopter then took off from the fuel staging area, and slowly hover taxied in a north-northwesterly direction over the water. Although the pilot had many flying hours using a longline and many hours using the water bucket on lightweight helicopters, it was the first time he was using them together while flying the Bell205, a medium-weight helicopter. The helicopter was approximately 1000feet from shore when the crew felt a vibration and heard a bang, which was followed by what seemed to be a loss of power. The pilot applied collective to avoid descending, pushed the cyclic forward to gain speed and ordered the loadmaster to jettison the water bucket. The helicopter lost altitude, pitched nose down, and banked to the right before striking the water. Both occupants exited the helicopter while it was sinking. Other helicopters operating on the fire arrived promptly on site. The crew was rescued by firefighters with a small motor boat. The helicopter rolled inverted and sank in approximately 25feet of water. The loadmaster was evacuated by helicopter to the local hospital. The pilot-in-command was first evacuated to the base camp where he was stabilized. He was then transported by ambulance to hospital where he arrived approximately four hours after the occurrence. At the time of the occurrence, the pilot-in-command was wearing the lap-belt, but was not wearing the shoulder harness. It is common practice for pilots flying vertical reference operations to leave the shoulder harness unfastened since considerable upper body movement is required to lean into the vertical reference bubble window during longline operations. The pilot-in-command suffered a broken back. The loadmaster wore both the lap-belt and the shoulder harness. He received only minor injuries. Neither the pilot nor the loadmaster was wearing a lifejacket as per the company operations manual, Part1, Chapter4, Section4.25, Operations over Water. The pilot-in-command did not know how to swim. Neither crew member was wearing a helmet; the use of helmets was not mandatory. Photo1. Damage to Bell 205 A-1, C-GADA The helicopter came to rest inverted approximately 1000feet from shore in about 25feet of water and silt, which totally obscured the water during salvage operations. The initial attempt to retrieve the helicopter by the cargo hook resulted in the lift beam being torn off and lost. The water bucket, the tail rotor, and all parts that had been separated from the airframe could not be located due to the lack of visibility under water. Once the helicopter was recovered, examination of the airframe confirmed a nose-down impact on the right side (Photo1). The main rotor blades had been severely damaged from impact with the water. Signs of delaminating of the re-enforcing straps near the blade roots, usually associated with blade coning, were not present. Coning is the result of upward blade movement if rotor rpm decays following a loss of power and application of collective. The examination revealed that the impact loads had also broken the four main transmission pylon mounts. The transmission remained attached to the airframe only by the hydraulic lines and the flight controls. During the impact, the rotor head contacted the mast. The mast was disassembled and examined; no pre-accident condition, which could have been causal to the accident, was revealed. The main power shaft between the engine and the transmission was a KAflex type. Only the connectors to the engine and transmission were recovered, with some of the flexible segments still attached. All fractures associated with the KAflex were examined and found to have resulted from overload. The hollow portion of the shaft grooved a circular imprint of the shaft ends on both the connectors. This could only have occurred if the shaft assembly had remained in position until impact. Records indicate that the helicopter was certified and equipped in accordance with current regulations and approved procedures, and was within weight and balance limits before and after the water bucket was released. The last 100-hour inspection was completed 12July2005. The helicopter was equipped with a Lycoming (Honeywell) model T53-13B turboshaft engine, serial number LE-O7556. The engine was last overhauled by Air Asia Company Ltd. on 10January2002 and installed on PK-UHJ, an Indonesian Bell205A-1 helicopter. Air Asia repaired the engine on 12August2003 for high oil consumption and re-installed it on PK-UHJ. That helicopter was imported to Canada in 2003and privately registered as C-GADA on 02April2004 to a company based in British Columbia. It was acquired by Hli-Express Inc. three weeks later and commercially registered on 22April2004. The engine was removed on 16September2004 and forwarded to Eagle Copters for a hot section inspection (HSI) and replacement of time-expired turbine disks. The engine was re installed on C-GADA on 09February2005. At the time of the accident, it had accumulated 171hours since the HSI and 993.3hours since overhaul. Following the occurrence, the engine was removed and forwarded to Honeywell's facilities in Phoenix, Arizona, United States, for examination. The teardown was attended on behalf of the TSB by an investigator from the National Transportation Safety Board. There are 31blades (part number 1-100-361-06) on the first stage compressor disk. Each blade has a locking tab (part number 1-100-505-02). These are single use only items and should be replaced at each disassembly. The examination revealed that all the locking tabs, locking the blades to the first stage compressor disk, were found unbent (see Photo2). All of the blades had moved back and there was rotational scoring on all aft blade platforms, with corresponding damage on the outer diameter of the vane support. The manufacturer had no history of known compressor blade walking incidences that would first manifest themselves as an aerodynamic instability leading to compressor surge/stall. This can be explained by the fact that reducing the gap between the trailing edge of the blade and the leading edge of the vane has no adverse effect on the airflow within the engine. The disassembled engine was returned to the TSB Engineering Laboratory. The additional test results are outlined in report LP046/2006 (Testing of Locking Tabs). The report shows that a calculated rearward acceleration in the vicinity of 2034g would have been required to unbend the tabs. The relatively low impact sustained by the helicopter, the forward direction of the helicopter during the impact, and the observations made during the testing suggest that it is unlikely that the first stage compressor blades moved aft during the accident, unbending the tabs. It is likely that the tabs were not replaced and bent, as required, during the last maintenance conducted on the compressor (Photo2) The engine teardown at the Honeywell facility also revealed that the following parts had been procured under a U.S. Army code, and their installation is not authorized in a certified engine: Power shaft bearing retainer assembly: part number 1-060-090-03, serial number33640.39 Left-hand nozzle assembly: part number 1-130-730-02, serial number3257041 Second-stage gas producer turbine nozzle: part number 1-120-000-14, serial number3313 These parts would have been exposed during the overhaul at the Air Asia facility, a Honeywell authorized repair facility. An overhaul requires that all parts be checked and recorded. The nozzle assembly and second-stage turbine nozzle would have been exposed at the last HSI done at the Eagle Copters facility. Installation was based on the availability of identification tags confirming the airworthiness of the parts. Control of aviation parts on components that were first designed and put in service for the military can be confusing, and even more so in the case of this model of engine (T53-L-13B) for which the U.S. Army owns the drawings. Although this version of the engine (T53-13B) is certified by the Federal Aviation Administration (FAA), a large quantity of parts in the Illustrated Parts Catalog (IPC) share the same part number as the military ones. Therefore, the identification on a data plate or the scribe on a part, along with its tag confirming its traceability, is not sufficient to attest that the part is authorized for commercial use. Its validity must be checked against a Commercial and Government Entity (CAGE) code, which identifies the manufacturer and the purchaser. These codes are available on the Business Identification Number Cross-reference System (BINCS) Web site. The CAGE code 81996 found scribed on the three unauthorized parts described earlier in the report refers to material being manufactured for the U.S. Army Aviation and Missile. For this occurrence engine, the proper CAGE code for these parts should have been91547. The tags do not include the CAGE code nor is it required. This can result in the issuance of a certificate of airworthiness without the benefit of complete and adequate documentation. The engine teardown report prepared by Honeywell indicates that there was no pre existing condition found in the engine that would have interfered with its normal operation. The type of damage to the engine was indicative of engine rotation and operation at the time of impact with the water. Supporting this assessment was the fact that molten aluminum was found splattered in the combustion chamber and on all turbine blades. This condition would require sustained combustion, which in turn requires engine rotation. Rotation at the time of impact was evidenced by several areas of rubbing and scoring, as follows: rotational scoring through about 60 degrees on the particle separator lower assembly half; leading edge blade tip corners were separated on nearly all of the blades of the first and second stage axial compressor with the remaining material bent opposite the direction of rotation; trailing edge of blades on the five axial compressor stages bent opposite to rotation; rotational scoring on about 200degrees on the centrifugal compressor shrouds; and foreign object damage2 on the five stages of the axial compressor (the first two stages showed heavier damage). The fuel control unit (FCU), modelTA-7, was tested at the Goodrich facilities, with a TSB technical investigator in attendance. The FCU and power turbine governor were found to be functional. All of the tested values were either within and/or slightly beyond the acceptance test procedure specification limits. Neither the functionally tested values nor the disassembly of the FCU disclosed any pre-existing conditions that would have interfered with normal engine operation. Teardown of the main transmission and free wheeling unit did not reveal any pre condition that would have led to a loss of rotor control. Engine compressor stall or surging has been known to leave impinge marks on the gears of the 42-degree gearbox or tail-rotor gearbox. The tail-rotor gearbox was not recovered. Examination of the 42-degree gearbox did not reveal any signs of impingement. The helicopter is equipped with warning lights that advise the pilot of the loss of important parameters, systems, or components. All instrument panel, annunciator panel, and vertical reference bubble window caution warning light bulbs, of which there are 46,were recovered from the wreckage and sent to the TSB Engineering Laboratory to determine their ON-OFF state at impact. TSB Engineering Laboratory report LP090/2005 concludes that none of the lamp filaments exhibited any of the characteristics normally associated with an incandescent filament when shocked. It is therefore likely that all the lamps were OFFat the time of impact. An engine warning light would typically turn ON between 5and 11seconds after a failure. A low rotor warning light would take about 3seconds. Neither the pilot-in-command nor the loadmaster remembers seeing any warning lights or hearing any warning horns during the occurrence. Fuel samples taken from the helicopter fuel tank, engine fuel filter, and ground pump were sent to the TSB Engineering Laboratory for analysis. TSB Engineering Laboratory report LP085/2005 concludes that the engine was fuelled by a mixture of JetA and 14.86percent by weight or more of 100LLaviation gasoline (AVGAS). An analysis of the fuel recovered from the FCU, conducted by Honeywell, showed 11percent by weight of AVGAS. Although the engine manufacturer does not include AVGAS as an approved fuel for the T53 engine, the engine is able to function without immediate harmful consequences. The FCU is designed for scheduling fuel of various specific gravities. AVGAS is an acceptable emergency fuel for the military version of this model of engine. The Socit de protection des forts contre le feu (SOPFEU) is responsible for the prevention, detection and suppression of forest fires in Quebec. During forest fire suppression operations, the SOPFEU will order fuel from the closest fuel wholesaler. Barrels are used, cleaned, refilled, and resealed at the wholesaler's distribution yard and then delivered to the customer. Because the wholesaler is delivering a product to an off-airport location, it need only abide by provincial regulations. An order of 40barrels of JetA1 fuel was placed by the SOPFEU on 15July2005 with the wholesaler in Sept-les, Quebec, about 100km from the base camp. However, 36barrels of JetA1 fuel and 4barrels of AVGAS were delivered. The 40barrels delivered were white in colour. The identifying stickers are white with black lettering. The markings on the identifying stickers affixed to the barrels showed the appropriate information specified in provincial regulations, in that they included type of fuel, date, batch number, and dangerous goods information. The only visible difference on the barrels were the words 100LLAVGAS and JETA1 (Photos3and4). Photo3. View of fuel barrels and identifying stickers Photo4. Fuel barrel identifying stickers This fire operation required four helicopters, all of which used JetA1 fuel. Since no other aircraft requiring AVGAS had been contracted, the helicopter operator was not concerned that there could be barrels of AVGAS mixed with the delivery. AVGAS is considered a Class1 petroleum product and under existing provincial regulations,a Class1 product over 45litres does not require any kind of colour coding of the container. However, a container under 45litres, containing a Class1 product, must be predominately red in colour. Therefore, by provincial law, the 205litre barrels of AVGAS do not have to differ in colour from a Class2 (Jetfuel) or a Class3 product. No colour differentiation of the identifying stickers is necessary. The different products in the containers were not visible to the user, and do have a different colour and smell. AVGAS is blue and Jet fuel is yellow. Workers loading the product at the wholesaler and those delivering the product to the SOPFEU had mistakenly mixed some AVGAS barrels with the JetA1 barrels. During the fuelling process, the helicopter pilots using the product mistakenly identified the AVGAS barrels as JetA1barrels. Transport Canada regulations define an aerodrome as, Any area of land, water (including the frozen surface thereof) or other supporting surface used or designed, prepared, equipped or set apart for use whether in whole or in part of the arrival and departure, movement or servicing of helicopter and includes any buildings, installations and equipment in connection therewith. The base camp and fuel cache from which the accident helicopter and three other helicopters were operating would be considered an aerodrome by definition. Distributors of a petroleum product at an aerodrome are subject to provincial regulations. Although federal standards exist to properly identify a petroleum product by colour of container, pump, or identifying sticker, these standards cannot be enforced. The Transport Canada Vertical Reference Flying Pilot's Guide explains that people have little or no depth perception beyond 15feet. A pilot flying longline operations must ensure an adequate scan of the surrounding area and not fixate on any one thing for too long so that the helicopter's speed, altitude, depth, and rate of closure can be adequately estimated. Objects in the periphery, ambient light, and shadows are some of the essential information necessary for the brain to properly assess the helicopter's position and movement. Longline operations require that the pilot position the helicopter in proximity to fixed objects, in this case preferably on the left side of the helicopter where the pilot is seated. The pilot must stop the helicopter's forward speed and maintain the helicopter's position relative to these objects constant while descending to fill the water bucket. It is equally important to climb enough to ensure that the water bucket is well clear of the water surface before transitioning to forward flight. At 1000feet from shore, the pilot would not have been able to adequately judge the helicopter's forward speed and altitude above the water. Had the water bucket inadvertently dragged on the water surface and entered the water, it would have acted as an anchor, abruptly restricting the aircraft's forward motion.